Eloy is a city in Pinal County, Arizona, United States, about 50 miles (80 km) northwest of Tucson and about 65 miles (105 km) southeast of Phoenix. According to the U.S. Census estimates in 2018, the population of the city is 19,391.
In 1902 the Southern Pacific Railroad named its switch here Eloi, which was adapted to the Spanish spelling. A town called Cotton City was established in 1918 but the post office used the shorter Eloy in 1919.
According to the U.S. Census of 2000, the city has a total area of 98.9 square miles (256 km2). The city offers a varied range of community facilities for its citizens. Outside the city limits, the city has a planning area of almost 560 square miles (1,500 km2).
As of the census of 2011, there were 16,964 people, 2,492 households, and 1,988 families residing in Eloy. The population density was 144.8 people per square mile (55.9/km²). There were 2,734 housing units at an average density of 38.1 per square mile (14.7/km²). The racial makeup of the city was 58% Hispanic or Latino, 5.32% Black or African American, 41% White, 4.48% Native American, 1.20% Asian, 0.11% Pacific Islander, 31.48% from other races, and 4.71% from two or more races.